1. Field of the Invention
This invention relates to fresh cheese-like food products and a process for their production, and more particularly it relates to novel fresh cheese-like food products which can be obtained by adding a thermally coagulable protein and a specific coagulant to milk and heating to effect coagulation, and a process for their production.
2. Description of the Prior Art
Heretofore, there have been known curd, milk curd and yoghurt as products obtained by coagulating milk.
The curd is a coagulum which is formed by adding a starter or an acid to whole milk or skimmed milk or reacting the latter with rennet. While the main component of the curd obtained by coagulating skimmed milk is protein containing almost no fat, the curd obtained from whole milk has a water content of 35-70% by weight, a fat content of 5-33% by weight and a protein content of 15-30% by weight. Curd is employed as the starting material for producing cheese.
The milk curd is that obtained by adding an acid to whole milk, heating to effect coagulation, filtering off the formed curd and pressing it, and has a composition of a water content of 50-60% by weight, a fat content of 15-20% by weight and a protein content of 15-20% by weight. This is not on the market as a commercial product, but is merely produced in some quarters for home consumption.
The yoghurt is a thick coagulated milk obtained by fermenting whole milk or skimmed milk, either as such or after partial concentration, using a specific lactic acid bacterium, and has a water content of 78-85% by weight, a fat content of 0.2-2.1% by weight and a protein content of 3.6-4.3% by weight.
However, all of these coagulated products are those obtained by coagulating milk under the acidic conditions of pH 6-4, and thus they inevitably exhibit acid taste.
On the other hand, although it is possible to obtain a coagulated product which does not exhibit acid taste by gelling milk by adding agar, gelatin or other gum matters, said coagulated product is not suitable for cooking purposes, because it dissolves by heating to a temperature even below the boiling point of water.
Casein which is the main component of milk is not easily coagulated by heating and does not form a uniform gel even by adding a coagulant other than acid and heating but exhibits such phenomenon as syneresis, and therefore it has been difficult to obtain a coagulated product from milk, which does not undergo decomposition of the gel structure even by heating to a temperature below the boiling point of water and also does not exhibit acid taste.